;+
; NAME:
; log_bins
;
;
; PURPOSE:
; create log spaced bins, useful for plotting spectra with histo_bins
;
;
; CATEGORY:
; stats
;
;
; INPUTS:
; MIN: minimum value of bins
; MAX: maximum value of bins
; NBINS: number of bins to create
;
;
; KEYWORD PARAMETERS:
; DOUBLE: return a double instead of a float
; NATURAL: do natural log spaced bins
;
;
; OUTPUTS:
; bins: the log spaced bins between min and max
;
;
; RESTRICTIONS:
; Requires scale_vector from David Fanning dfanning.com
;
;
; EXAMPLE:
; IDL> print, log_bins(0.1, 10, 10)
;      0.100000     0.166810     0.278256     0.464159     0.774264
;      1.29155      2.15443      3.59381       5.99484      10.0000
;
;
;
; MODIFICATION HISTORY:
;
;       Tue Sep 29 10:17:28 2009, Brian Larsen
;		forget the /double to scale_vector (fixed)
;       Wed Aug 12 14:06:28 2009, Brian Larsen
;		written and tested 
;
;-
FUNCTION log_bins, min, max, nbins,  DOUBLE = double

     IF NOT keyword_set(double) THEN $ 
        bins = 10.^scale_vector(findgen(nbins), alog10(min)/alog10(10), alog10(max)/alog10(10)) $
     ELSE $
        bins = 10.^scale_vector(dindgen(nbins), alog10(min)/alog10(10), alog10(max)/alog10(10), $
                                /double)
    
  RETURN, bins
END